OP0057 RESPONSE TO INJECTION CAN PREDICT OUTCOMES OF FEMOROACETABULAR IMPINGEMENT
Authors: E. Campos Martins, D. Almeida Gomes, H. De Brito Fontana, D. Araujo Fernandes, F. De Souza Neves
Journal: Annals of the Rheumatic Diseases (2022)

Background Femoroacetabular impingement syndrome (FAIS) is a highly prevalent painful disorder that is considered a risk factor for hip osteoarthritis. In order to relieve pain and improve cartilage preservation, surgery is often performed. However, many operated patients do not show satisfactory outcomes. Reliable diagnostic tests that can inform prognosis of surgery in patients with FAIS are needed for optimized indications and contraindications to surgery. Objectives This systematic review aimed to answer the following question: “Can the response to intra-articular anesthetic injections be used to predict surgical outcomes in patients with FAIS?”. Methods This study was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) statement. Embase, CINAHL, LILACS, PubMed, SCOPUS, SPORTDiscuss, The Cochrane Library, and Web of Science databases were screened. All studies that assessed the capability of the response to intra-articular anesthetic injections in predicting surgical outcomes for patients with FAIS were considered eligible. Study selection and data collection were performed by three independent reviewers. Risk of bias of the included studies was assessed through the QUIPS tool. Results Seventeen articles were selected for full-text reading, of which 6 were considered eligible and included for analysis [1-6]. A summary of the studies’ descriptive characteristics can be found in the Table 1. A high risk of bias due to study attrition and the presence of confounding factors was observed for all included studies. Five out of six studies [1-4,6] presented “high risk“ of bias associated to the prognostic factor measurement. A high overall risk of bias was evidenced by QUIPS for all studies (Figure 1). From 6 included studies, 5 indicated that the response to intra-articular injections can be useful in the prediction of surgical outcomes [2-6]. Table 1. Author Mean Age N (Female) Injection Content Time for pain assessment after injection (Way) Intervention group (Control) Follow-up time after surgery (Score used) Results Ayeni ? (16-62) 52 (30) Bupivacaine + prednisolone Daily for 2 weeks (provocative activities) 42 with any pain relief (10) 6 months (mHHS) Likelihood Ratio of reaching &gt;70 points (LR) for responders was 1.15; LR for nonresponders was 0.57 (p&gt;0.05) Chinzei 36.7 ± 14.7 49 (27) Lidocaine 2 weeks (?) 30 with &gt;50% of pain relief (19) 12 months (mHHS) Good responders showed better mHHS, pre- (p=0.048) and post-operatively (p=0.026) Gao 36.5 (16-65) 78 (41) Lidocaine + betamethasone 10 min and 1 week (routine tasks) 33 with &gt;50% of pain relief (3) 22.8 ± 9.7 months (mHHS) 100% of good responders surpassed the MCID, while only 1/3 of poor responders achieved it Krych 37.6 ± 14.0 319 (?) Variable 2 weeks, reporting the relief of the first 24h (?) 70 with &gt;50% of pain relief (26) 11–30 months (HOS and mHHS) For Tönnis grade 1 patients, good responders had higher HOS-SS (p=0.03) Li 38.6 ± 14.9 60 (33) Lidocaine + ropivacaine 30 min (physical tests) - 12 months (mHHS and iHOT-12) Correlation between iHOT after injection and iHOT at 12 months after surgery (r=0.784; p&lt;0.01) Mujahed ? (16-65) 242 (?) Lidocaine + betamethasone ? (?) 120 with any pain relief (88) 24 months (HOS and mHHS) Responders had greater improvement (p&lt;0.05) in all metrics, except for MCID at mHHS (p=0.24) Figure 1. Conclusion Although there seems to be some evidence supporting the use of intra-articular anesthetic injections to predict surgical outcomes in patients with FAIS, it is not conclusive. Future studies taking into account the various possible sources of bias in prognostic studies are needed. Standardizing and optimizing injection protocols as well as post-injection pain assessment and outcomes measurements are also essential to fill this gap. References [1]OR Ayeni et al., Knee Surg Sports Traumatol Arthrosc 22 (4), 801 (2014) [2]N Chinzei et al., Eur J Orthop Surg Traumatol 30 (4), 737 (2020) [3]G Gao et al., Arthroscopy 37 (1), 128 (2021) [4]AJ Krych et al., Arthroscopy 32 (8), 1592 (2016) [5]S Li et al., Orthop Surg 13 (6), 1810 (2021) [6]T Mujahed et al., Orthop J Sports Med 9 (11), 2021 Disclosure of Interests None declared.